Driving controlling apparatus for air conditioner having plural compressors and method thereof

ABSTRACT

A driving controlling apparatus for an air conditioner having a plurality of compressors, and a method thereof. The apparatus comprises a flow amount distribution resistor installed at an outlet of an expansion valve, for passing a certain amount of refrigerant; and a controlling unit for detecting a current load and outputting a control signal so as to introduce a certain amount of refrigerant into the flow amount distribution resistor based on a driving mode corresponding to the detected load.

RELATED APPLICATION

The present disclosure relates to subject matter contained in priorityKorean Application No. 10-2005-0073499, filed on Aug. 10, 2005, which isherein expressly incorporated by reference in its entirely.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a driving controlling apparatus for anair conditioner having a plurality of compressors, and a method thereof,and more particularly, to a driving controlling apparatus for an airconditioner having a is plurality of compressors capable of preventingincrease of consumption power and decrease of a driving efficiency of asystem due to an excessive refrigerant flow, and a method thereof.

2. Description of the Background Art

Generally, an air conditioner serves to lower an indoor temperature byusing a refrigerating cycle of a refrigerant compressed into a hightemperature and a high pressure by a compressor.

When the air conditioner is provided two compressors, the twocompressors are selectively driven according to a refrigerating load.

FIG. 1 is a view showing a construction of an air conditioner having twocompressors in accordance with the related art.

As shown, the related art air conditioner comprises a first compressor10 and a second compressor 20 selectively driven for varying acompression amount of a refrigerant; a condenser 1 for condensing arefrigerant compressed by the first compressor 10 and the secondcompressor 20; an expansion valve 2 for expanding a refrigerantcondensed by the condenser 1; and an evaporator 3 for heat-exchanging arefrigerant expanded by the expansion valve 2 with indoor air.

It is assumed that the first compressor 10 is an inverter-type smallcapacity compressor and the second compressor 20 is a constantspeed-type large capacity compressor.

Suction pipes 11 and 21 of the first compressor 10 and the secondcompressor 20 are connected to hoses 31 and 32 diverged from a suctionhose 30, respectively. Also, discharge pipes 12 and 22 of the firstcompressor 10 and the second compressor 20 are connected to hoses 41 and42 diverged from a discharge hose 40, respectively.

Suction valves 33 and 34 and the discharge valves 43 and 44 selectivelyopened and closed by manually or by a controlling unit (not shown) suchas a microcomputer are connected to the diverged hoses 31, 32, 41, and42, respectively.

The air conditioner having two compressors performs a refrigeratingoperation by selectively driving the first compressor 10 and the secondcompressor 20 according to a refrigerating load.

More concretely, when the refrigerating load is small, only the firstcompressor 10 is driven. When the refrigerating load is medium, only thesecond compressor 20 is driven. On the contrary, when the refrigeratingload is large, both the first compressor 10 and the second compressor 20are driven thereby to vary a compression amount of a refrigerantrequired for a cooling operation.

When a refrigerant is compressed by the first compressor 10 or thesecond compressor 20 so as to perform a refrigerating cycle, lubricantinside the first compressor 10 and the second compressor 20 is mixedwith the refrigerant thus to be discharged. The discharged lubricantperforms a refrigerating cycle, and then is re-sucked into the firstcompressor 10 and the second compressor 20 via an accumulator (notshown).

Herein, a refrigerant amount to be introduced into the compressor is seton the basis of a compressor having a capacity of 100% for a constantcooling capability.

However, when the system is driven in a minimum capacity driving mode(driving of only one compressor), the refrigerant amount to beintroduced into the compressor having a capacity of 100% increases aconsumption power due to an excessive refrigerant amount thereby tolower a driving efficiency of the system.

Furthermore, under a state that the air conditioner having a pluralityof compressors is driven in an over-load driving mode, when atemperature of a refrigerant discharged from the compressor is increasedmore than a certain degree, the capacity of the compressors is decreasedor the compressors are turned off thereby to maintain a reliability ofthe system.

When the compressors are frequently turned off, an indoor comfortabledegree is lowered.

That is, when a temperature of a refrigerant discharged from thecompressors is increased more than a certain degree, the compressors arefrequently turned off. Accordingly, cool air is not constantly suppliedindoors thereby to cause the indoor comfortable degree to be lowered.

SUMMARY OF THE INVENTION

Therefore, an object of the present invention is to provide a drivingcontrolling apparatus for an air conditioner having a plurality ofcompressors capable of preventing increase of consumption power anddecrease of a driving efficiency of a system due to an excessiverefrigerant amount even if the compressors of the air conditioner havinga maximum refrigerant amount are driven in a minimum capacity drivingmode, in which a refrigerant cooled by an expansion is partiallyheat-exchanged by a condensing unit thus to lower a condensationtemperature, and a method thereof.

To achieve these and other advantages and in accordance with the purposeof the present invention, as embodied and broadly described herein,there is provided a driving controlling apparatus for an air conditionerhaving a plurality of compressors, comprising: a flow amountdistribution resistor installed at an outlet of an expansion valve, forpassing a certain amount of refrigerant; and a controlling unit fordetecting a current load and outputting a control signal so as tointroduce a certain amount of refrigerant into the flow amountdistribution resistor based on a driving mode corresponding to thedetected load.

According to another aspect of the present invention, there is provideda driving controlling apparatus for an air conditioner having aplurality of compressors, comprising: a flow amount distributionresistor installed at an outlet of an expansion valve, for passing acertain amount of refrigerant; a switching unit installed at an outletof the flow amount distribution and switched by a control signal, forcontrolling a flow of a refrigerant discharged from the flow amountdistribution resistor; a condenser heat exchanging unit for lowering atemperature of a condenser by using a refrigerant introduced through theswitching unit, and introducing the refrigerant into an accumulator; anda controlling unit for detecting a current load, selecting a drivingmode based on the detected load thereby driving the system, andoutputting a control signal so as to control the switching unit based onthe selected driving mode.

To achieve these and other advantages and in accordance with the purposeof the present invention, as embodied and broadly described herein,there is also provided a driving controlling method for an airconditioner having a plurality of compressors, comprising: detecting acurrent load and selecting a compressor driving capacity based on thedetected load; and analyzing the compressor driving capacity, andlowering a temperature of a condenser by using a certain amount ofrefrigerant based on the analyzed result.

The foregoing and other objects, features, aspects and advantages of thepresent invention will become more apparent from the following detaileddescription of the present invention when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of theinvention.

In the drawings:

FIG. 1 is a view showing a construction of an air conditioner having twocompressors in accordance with the related art;

FIG. 2 is a block diagram showing a driving controlling apparatus for anair conditioner having a plurality of compressors according to thepresent invention;

FIG. 3 is a flowchart showing a driving controlling method for an airconditioner having a plurality of compressors according to the presentinvention;

FIG. 4 is a schematic view showing a condenser and a heat exchangingunit of FIG. 2 by a double tube heat exchanging method; and

FIG. 5 is a schematic view showing the condenser and the heat exchangingunit of FIG. 2 by a capillary tube heat exchanging method.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings.

Hereinafter, a driving controlling apparatus for an air conditionerhaving a plurality of compressors capable of preventing increase ofconsumption power and decrease of a driving efficiency of a system dueto an excessive refrigerant flow even if the compressors of the airconditioner having a maximum refrigerant amount are driven in a minimumcapacity driving mode, and a method thereof.

FIG. 2 is a block diagram showing a driving controlling apparatus for anair conditioner having a plurality of compressors according to thepresent invention.

As shown in FIG. 2, a driving controlling apparatus for an airconditioner having a plurality of compressors according to the presentinvention comprises: a switching unit 100; a condenser heat exchangingunit 200; a controlling unit 300; and a flow amount distributionresistor 400.

The flow amount distribution resistor 400 is installed at a flow pathdiverged from refrigerant path positioned at an outlet of an expansionvalve, and passes a certain amount of refrigerant.

The flow amount distribution resistor 400 has a preset resistance valuefor passing an optimum amount of refrigerant obtained by an experiment.

The switching unit 100 is installed at an outlet of the flow amountdistribution resistor 400 and is switched by a control signal, therebycontrolling a flow of a refrigerant discharged from the flow amountresistor 400.

The condenser heat exchanging unit 200 lowers a temperature of acondenser by using a refrigerant introduced through the switching unit100, and introduces the refrigerant to an accumulator.

As shown in FIG. 4, the condenser heat exchanging unit 200 lowers atemperature of the condenser by a double tube heat exchanging methodshown in FIG. 4. As shown in FIG. 5, the condenser heat exchanging unit200 lowers a temperature of the condenser by a capillary tube heatexchanging method shown in FIG. 5.

The controlling unit 300 detects a current load, and selects a drivingmode based on the detected load thus to drive the system. Then, thecontrolling unit 300 outputs a control signal for controlling theswitching unit 100 based on the selected driving mode.

More concretely, when the compressors are driven in a maximum capacitydriving mode, the controlling unit 300 turns off the switching unit 100so that a refrigerant can be prevented from flowing to the condenserheat exchanging unit 200, and then introduces a refrigerant outputtedfrom an expansion valve into an evaporator.

On the contrary, when the compressors are in a minimum capacity drivingmode, the controlling unit 300 turns on the switching unit 100 so that arefrigerant discharged from the expansion valve can be partiallyintroduced to the condenser heat exchanging unit 200 via the flow amountdistribution resistor 400.

The operation of the driving controlling apparatus for an airconditioner having a plurality of compressors will be explained withreference to FIG. 3.

First, the controlling unit 300 detects a current driving load (SP1),and selects a compressor driving capacity based on the detected load(SP2).

When a current driving load is judged to be a normal load, thecontrolling unit 300 selects a maximum capacity driving mode. On thecontrary, when a current driving load is judged to be a low load, thecontrolling unit 300 selects a minimum capacity driving mode.

For instance, when the compressors are driven in a maximum capacitydriving mode, two compressors are simultaneously driven. On thecontrary, when the compressors are driven in a minimum capacity drivingmode, only one compressor, mainly one compressor having a smallercapacity is driven.

Then, the controlling unit 300 analyzes the selected driving mode (SP3),and controls a refrigerant amount based on the analyzed result (SP4).Next, the controlling unit 300 turns on the switching unit 100 so as toprevent a temperature of a refrigerant discharged from the compressorfrom being increased (SP6).

More concretely, when the compressors are driven in a maximum capacitydriving mode, the controlling unit 300 turns off the switching unit 100so as to completely use introduced refrigerants, thereby completelyintroducing the refrigerant discharged from the expansion valve into theevaporator (SP5).

On the contrary, when the compressors are driven in a minimum capacitydriving mode, the controlling unit 300 turns on the switching unit 100so that the refrigerant discharged from the expansion valve can bepartially introduced to the condenser heat exchanging unit 200 via theflow amount distribution resistor 400. Accordingly, a temperature of thecondenser is lowered, and the system is driven with the rest refrigerant(SP6).

As the result, when the compressors are driven in a minimum capacitydriving mode, the system is driven with an optimum refrigerant therebyto reduce a consumption power.

When the system is driven in an over-load state (where a driving load ishigher than a normal load), the controlling unit 300 turns on theswitching unit 100 in the same manner as the operation in the minimumcapacity driving mode thereby to lower the temperature of the condenser.Accordingly, a temperature of a refrigerant discharged from thecompressor is lowered, thereby preventing an OFF state of the compressordue to a temperature rise of the refrigerant discharged from thecompressor.

The over-load driving mode is set by a user. For instance, the over-loaddriving mode is set when a user's preset temperature is different froman indoor temperature by more than a certain degree, or an outdoortemperature is higher than a certain degree.

That is, in the present invention, a refrigerant amount is distributedin a minimum capacity driving mode or an over-load driving mode except anormal driving mode.

In the driving controlling apparatus for an air conditioner having aplurality of compressors according to the present invention, arefrigerant cooled by an expansion is partially heat-exchanged by thecondenser, thereby having a lowered condensation temperature.Accordingly, even if the air conditioner having a maximum refrigerantamount is driven in a minimum capacity driving mode, a consumption powerincrease and a driving efficiency decrease of the system due to anexcessive refrigerant flow are prevented.

Furthermore, in the present invention, when the system is driven underan sover-load state, a refrigerant cooled by an expansion is partiallyheat-exchanged by the condenser, thereby having a lowered condensationtemperature. Accordingly, a temperature of the refrigerant dischargedfrom the compressor is prevented from being increased more than acertain degree, thereby enhancing a reliability of the system.

As the present invention may be embodied in several forms withoutdeparting from the spirit or essential characteristics thereof, itshould also be understood that the above-described embodiments are notlimited by any of the details of the foregoing description, unlessotherwise specified, but rather should be construed broadly within itsspirit and scope as defined in the appended claims, and therefore allchanges and modifications that fall within the metes and bounds of theclaims, or equivalents of such metes and bounds are therefore intendedto be embraced by the appended claims.

1. A driving controlling apparatus for an air conditioner having aplurality of compressors, comprising: a flow amount distributionresistor installed at an outlet of an expansion valve, for passing acertain amount of refrigerant; and a controlling unit for detecting acurrent load and outputting a control signal so as to introduce acertain amount of refrigerant into the flow amount distribution resistorbased on a driving mode corresponding to the detected load.
 2. Theapparatus of claim 1, wherein the flow amount distribution resistor isinstalled at a flow path diverged from a refrigerant path positioned atthe outlet of the expansion valve.
 3. The apparatus of claim 1, furthercomprising a switching unit installed at the outlet of the flow amountdistribution resistor and switched by a control signal, for controllinga flow of a refrigerant discharged from the flow amount distributionresistor.
 4. The apparatus of claim 1, further comprising a condenserheat exchanging unit for lowering a temperature of a condenser by usinga refrigerant introduced through the switching unit, and introducing therefrigerant into an accumulator.
 5. The apparatus of claim 1, whereinwhen the compressors are driven in a maximum capacity driving mode, thecontrolling unit turns off the switching unit so as to shield arefrigerant flow to the condenser heat exchanging unit, and therebyintroduces a refrigerant discharged from the expansion valve to anevaporator.
 6. The apparatus of claim 1, wherein when the compressorsare driven in a minimum capacity driving mode (or an over-load drivingmode), the controlling unit turns on the switching unit thereby topartially introduce a refrigerant discharged from the expansion valve tothe condenser heat exchanging unit via the flow amount distributionresistor.
 7. The apparatus of claim 1, wherein the flow amountdistribution resistor has a preset resistance value for passing anoptimum refrigerant.
 8. The apparatus of claim 4, wherein the condenserheat exchanging unit lowers a temperature of the condenser by a doubletube heat exchanging method.
 9. The apparatus of claim 4, wherein thecondenser heat exchanging unit lowers a temperature of the condenser bya capillary tube heat exchanging method.
 10. A driving controllingapparatus for an air conditioner having a plurality of compressors,comprising: a flow amount distribution resistor installed at an outletof an expansion valve, for passing a certain amount of refrigerant; aswitching unit installed at an outlet of the flow amount distributionand switched by a control signal, for controlling a flow of arefrigerant discharged from the flow amount distribution resistor; acondenser heat exchanging unit for lowering a temperature of a condenserby using a refrigerant introduced through the switching unit, andintroducing the refrigerant into an accumulator; and a controlling unitfor detecting a current load, selecting a compressor driving capacitybased on the detected load, and outputting a control signal so as tocontrol the switching unit based on the selected driving mode.
 11. Theapparatus of claim 10, wherein the flow amount distribution resistor isinstalled at a flow path diverged from a refrigerant path positioned atthe outlet of the expansion valve.
 12. The apparatus of claim 10,wherein when the compressors are driven in a maximum capacity drivingmode, the controlling unit turns off the switching unit so as to shielda refrigerant flow to the condenser heat exchanging unit, and therebyintroduces a refrigerant discharged from the expansion valve to anevaporator.
 13. The apparatus of claim 1, wherein when the compressorsare driven in a minimum capacity driving mode (or an over-load drivingmode), the controlling unit turns on the switching unit thereby topartially introduce a refrigerant discharged from the expansion valve tothe condenser heat exchanging unit via the flow amount distributionresistor.
 14. The apparatus of claim 10, wherein the flow amountdistribution resistor has a preset resistance value for passing anoptimum refrigerant.
 15. The apparatus of claim 10, wherein thecondenser heat exchanging unit lowers a temperature of the condenser bya double tube heat exchanging method.
 16. The apparatus of claim 10,wherein the condenser heat exchanging unit lowers a temperature of thecondenser by a capillary tube heat exchanging method.
 17. A drivingcontrolling method for an air conditioner having a plurality ofcompressors, comprising: detecting a current load and selecting acompressor driving capacity based on the detected load; and analyzingthe compressor driving capacity, and lowering a temperature of acondenser by using a certain amount of refrigerant based on the analyzedresult.
 18. The method of claim 17, wherein the step of lowering atemperature of a condenser comprises introducing a refrigerantdischarged from the expansion valve into an evaporator when thecompressors are driven in a maximum capacity driving mode.
 19. Themethod of claim 17, wherein the step of lowering a temperature of acondenser comprises partially introducing a refrigerant discharged fromthe expansion valve into the condenser heat exchanging unit via the flowamount distribution resistor when the compressors are driven in aminimum capacity driving mode.
 20. The method of claim 17, wherein thestep of lowering a temperature of a condenser comprises lowering atemperature of the condenser by the condenser heat exchanging unit witha capillary tube heat exchanging method.
 21. The method of claim 17,wherein the step of lowering a temperature of a condenser compriseslowering a temperature of the condenser by the condenser heat exchangingunit with a double tube heat exchanging method.